Swamp

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Xathrid Gorgon

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
{2}{B}, {T}: Put a petrification counter on target creature. It gains defender and becomes a colorless artifact in addition to its other types. Its activated abilities can't be activated. (A creature with defender can't attack.)

Dauthi Voidwalker

Shadow (This creature can block or be blocked by only creatures with shadow.)
If a card would be put into an opponent's graveyard from anywhere, instead exile it with a void counter on it.
{T}, Sacrifice this creature: Choose an exiled card an opponent owns with a void counter on it. You may play it this turn without paying its mana cost.

Cabal Coffers

{2}, {T}: Add {B} for each Swamp you control.

Dark Depths

Dark Depths enters with ten ice counters on it.
{3}: Remove an ice counter from Dark Depths.
When Dark Depths has no ice counters on it, sacrifice it. If you do, create Marit Lage, a legendary 20/20 black Avatar creature token with flying and indestructible.

Contaminated Bond

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Whenever enchanted creature attacks or blocks, its controller loses 3 life.

Gray Merchant of Asphodel

When this creature enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

Mortuary Mire

This land enters tapped.
When this land enters, you may put target creature card from your graveyard on top of your library.
{T}: Add {B}.

Thespian's Stage

{T}: Add {C}.
{2}, {T}: This land becomes a copy of target land, except it has this ability.

Moaning Wall

Defender
Cycling {2} ({2}, Discard this card: Draw a card.)

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Contamination

At the beginning of your upkeep, sacrifice this enchantment unless you sacrifice a creature.
If a land is tapped for mana, it produces {B} instead of any other type and amount.

Dread Presence

Whenever a Swamp you control enters, choose one —
• You draw a card and you lose 1 life.
• This creature deals 2 damage to any target and you gain 2 life.

Dark Ritual

Marit Lage

Vampiric Link

Enchant creature
Whenever enchanted creature deals damage, you gain that much life.

Murder

Stuffy Doll

Indestructible
As this creature enters, choose a player.
Whenever this creature is dealt damage, it deals that much damage to the chosen player.
{T}: This creature deals 1 damage to itself.

Bojuka Bog

This land enters tapped.
When this land enters, exile target player's graveyard.
{T}: Add {B}.

Wall of Souls

Defender (This creature can't attack.)
Whenever this creature is dealt combat damage, it deals that much damage to target opponent or planeswalker.

Sleeper Agent

When this creature enters, target opponent gains control of it.
At the beginning of your upkeep, this creature deals 2 damage to you.

Barren Moor

This land enters tapped.
{T}: Add {B}.
Cycling {B} ({B}, Discard this card: Draw a card.)

Festering Wound

Enchant creature
At the beginning of your upkeep, you may put an infection counter on this Aura.
At the beginning of the upkeep of enchanted creature's controller, this Aura deals X damage to that player, where X is the number of infection counters on this Aura.

Crypt Ghast

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever you tap a Swamp for mana, add an additional {B}.

Soldier

Akroan Horse

Defender
When this creature enters, an opponent gains control of it.
At the beginning of your upkeep, each opponent creates a 1/1 white Soldier creature token.